The intertidal actinian Anemonia sulcata is known to harbour yellow-brown algal symbionts which are similar in appearance to the zooxanthellae of hermatypic, or reef-building, corals and a number of other invertebrate species. The cytochemistry and structural morphology of the zooxanthella has been studied by light and electron microscopy, to help define it taxonomically and to reveal something about its relations with the actinian. These investigations confirm that it is a dinoflagellate and have revealed several structural adaptations which are formed as a result of the peculiar mode of life adopted by this alga. Of significance is the fine structure of the periplast, which may have a considerable bearing upon the type of relationship which can exist between the host and its symbiont. These findings are discussed in terms of other known instances of algal-invertebrate symbiosis.

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The taxonomy and nltrastructure of zooxanthellae from 6 species of Pacific giant clam have been studied from cultures. Comparison with type material shows that all of the isolates are Symbiodinium microadriaticum, a symbiotic dinoflagellate originally recorded from coelenterates in the Caribbean. Specific criteria for the identification of this organism are discussed, and their value to the comparative taxonomy of marine zooxanthellae is noted.

Photosynthetically enhanced calcification has been studied in the hermatypic coral, Acropora cervicornis . The rate in the light is directly proportional to the intensity of illumination between 0 and 10500 lx. Sodium azide, sodium cyanide, 2, 4-dinitrophenol (2, 4-DNP), pentachlorophenol and carbonyl cyanide, m -chlorophenyl hydrazone (CCCP) inhibit light (i. e. photosynthetically) dependent rates. With the exception of sodium azide, this may be attributed to an inhibition of oxidative phosphorylation. Dark rates of calcification are unaffected by the addition of these compounds.

One proposed means of increasing use of both transit and bicycles is to replace long automobile trips with “bike and ride” trips. In this study, a stated-preference survey was conducted using hypothetical scenarios within which respondents ranked their preferences for making a work trip by automobile only, park and ride, or bike and ride. The survey addressed numerous potential factors that might influence this choice, including three policy variables that were systematically varied in the scenarios: on-street bicycle facility type, bicycle parking facility type, and bicycle access distance to transit. The survey data are summarized and used to estimate discrete choice models. A nested logit choice model was developed as the preferred model. From this model, inferences are drawn about many factors. Conclusions are drawn about the three main policy variables. In short, the results support the notion that bicycle lockers are the preferred parking facility to increase bike and ride use. The results also indicate that bike lanes are superior to wide curb lanes as an incentive for casual and inexperienced cyclists, but that bike lanes and wide curb lanes are an identical incentive for experienced cyclists.